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You can post a response to any post, not only the most recent post in a topic. To reply simply click on the post you wish to respond to, then when viewing the post click the "Reply" link below the message. Now fill your response in to the form displayed into your web browser. In general you can just type "plain text" to compose your reply, although more advanced formatting is also possible (see the help file for details). If you want to see how your response will look click on the "Preview Message" button below the input form. When previewing your message you will see your formatted message at the top of the page, but can continue editing it in the form below. After previewing your message (or before previewing it if you never make mistakes) click the "Submit Reply" button below the message to post the message. Remember that all messages posted to the forum are viewable by anyone. You can edit messages you posted yourself by viewing the message, and clicking on the "Edit" button below the message.
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